Powder constant-volume feeder

Abstract

A powder constant-volume feeder includes a canister having on the inner surface thereof a fin for transferring powder upwards and is inclined to form a return portion for the powder which has been transferred by the fin. A bucket wheel has a plurality of buckets for continuously transferring the powder from the interior of the return portion to a powder hopper. The powder hopper receives the powder from the interior of the buckets of the bucket wheel. A constant volume of powder can thus be fed continously at a constant bulk density.

What is claimed is: 
     
       1. A powder constant-volume feeder including: a canister having on the inner surface thereof a fin for transferring powder upwards and being inclined to form a return portion for the powder which has been transferred by said fin;   a bucket wheel having a plurality of buckets for transferring the powder from said return portion to a powder hopper continuously; and   said powder hopper for receiving therein the powder from the interior of the buckets of said bucket wheel.   
     
     
       2. A powder-constant volume feeder according to claim 1, wherein said canister includes at least one fin. 
     
     
       3. A powder constant-volume feeder according to claim 1, wherein said bucket wheel has an inner surface comprising concaves and convexes, the concaves serving as said buckets. 
     
     
       4. A powder constant-volume feeder according to claim 1, wherein a multitude of pockets of an L-shaped section are provided along the inner surface of said bucket wheel, the pockets serving as said buckets. 
     
     
       5. A powder constant-volume feeder according to claim 1, wherein said powder hopper is provided at the upper portion thereof with a gas inlet pipe and also provided at the lower portion thereof with a gas outlet pipe. 
     
     
       6. A powder constant-volume feeder according to claim 5, wherein said canister has an upper opening which is covered with a cover with a retainer fitted in the central part of said cover and hermetically sealed with a gas seal, said retainer holding both said inlet and outlet pipes. 
     
     
       7. A powder constant-volume feeder according to claim 6, wherein both said inlet and outlet pipes extend through a single shaft.